Question

What is the molarity (M) of a solution composed of 5.85 grams of potassium iodide (KI) dissolved in enough water to make 0.125 liters of solution?

a) 0.25 M
b) 0.75 M
c) 0.125 M
d) 1.25 M

Answer 1

To find the molarity of the solution, divide the number of moles of solute by the volume of the solution in liters. In this case, the molarity is approximately 0.282 M.

Step-by-step explanation:

To find the molarity of the solution, we need to first calculate the number of moles of potassium iodide (KI) using its molar mass. The molar mass of KI is 39.10 g/mol (39.10 g/mol for K and 126.90 g/mol for I).

Number of moles of KI = 5.85 g / 166.00 g/mol = 0.03529 mol

Next, we can calculate the molarity using the formula:

Molarity (M) = number of moles / volume of solution (in liters)

Molarity = 0.03529 mol / 0.125 L = 0.28232 M

Therefore, the molarity of the solution is approximately 0.282 M.